Extra-corporeal medical instrument electrical connector

ABSTRACT

An electrical connector for attaching wires extending from a patient to an extra-corporeal medical instrument - resilient electrically conductive jaws grip an axially inserted wire leading from the patient. A collet peripherally mounted on the jaws adjustably deforms them exerting a compressive clamping force on the wire. The collet and jaw assembly is appropriately keyed to a complementary aperture in the instrument panel and affixed thereto by a threaded locking member. The locking member is electrically conductive thereby forming a feed through of the instrument panel. As the locking member engages a complementary threaded portion on the distal end of the jaws a bearing force is applied thereby affixing the entire assembly to the panel.

United States Patent 1 Berkovits et al.

in] 3,824,556 1 July 1 1974 EXTRA-CORPOREAL MEDICAL INSTRUMENTELECTRICAL CONNECTOR [73] Assignee: American Optical Corporation,

Southbridge, Mass.

[22] Filed: Apr. 13, 1972 [21] Appl. No.: 243,717

[52] US. Cl. 339/268 S [51] Int. Cl H0lr 7/16 [58] Field of Search339/268, 270, 214, 217 R, 339/126, 130

[ 56} References Cited UNITED STATES PATENTS 1,267,959 5/1918 Becker339/268 S 1,342,819 6/1920 v Lake 339/268 S 1,802,381 4/1931 Hofbauer339/268 S 2,463,144 3/1949 Buchanan 339/268 S 2,581,500 l/l952Schoonmaker 339/268 S 2,962,691 11/1960 Mande et a1. 339/214 R FOREIGNPATENTS OR APPLICATIONS 323714 1/1930 Great Britain... 339/268 S 894,9763/1944 France ..339/268S Primary Examiner.lames R. Boler AssistantExaminer-Peter Nerbun Attorney, Agent, or Firm-Joel Wall; William C.Nealon; Howard R. Berkenstock, Jr.

ABSTRACT An electrical connector for attaching wires extending from apatient to an extra-corporeal medical instrument resilient electricallyconductive jaws grip an axially inserted wire leading from the patient.A collet peripherally mounted on the jaws adjustably deforms themexerting a compressive clamping force on the wire. The collet and jawassembly is appropriately keyed to a complementary aperture in theinstrument panel and affixed thereto by a threaded locking member. Thelocking member is electrically conductive thereby forming a feed throughof the instrument panel. As the locking member engages a complementarythreaded portion on the distal end of the jaws a bearing force isapplied thereby affixing the entire assembly to the panel.

5 Claims, 4 Drawing Figures TO PATIENT EXTRA-CORPOREAL MEDICALINSTRUMENT ELECTRICAL CONNECTOR BACKGROUND OF THE INVENTION Thisinvention relates generally to electrical connectors used to attachwires extending from a patient undergoing examination or treatment to aremote extracorporeal medical instrument. It more particularly re-SUMMARY OF THE INVENTION lates to a feed through electrical connectorused in conl y deforms the l to exert a Compressive pjunction with anextra-corporeal heart stimulation device.

In the use of electrical medical instrumentation it is frequentlyessential that any disconnection of the patient from the device beavoided. In the instance of a heart stimulation instrument suchdisconnection can often lead to catastrophic results. The applicantsinvention is directed to minimizing this problem-while still affordingease of use and convenience for hospital personnel.

Electrical terminations used in existing commercial equipment consistofa shaft and a threaded collar. The wire is inserted through atransverse hole in the shaft and the threaded collar is used to compressthe wire in the hole thereby providing a locking of the wire as well asan intimate electrical connection. Another means of electricalconnection utilizes what is known as banana plugs. These terminationscomprise shafts, to which the wire is affixed, having resilient membersaxially aligned along the length of the shaft. The shaft is theninserted into a complementary channel or opening which compresses theresilient members thereby providing a biased or spring loaded electricalconnection. Anyone at all knowledgeable of instrumentation or theelectrical fields of practice are unavoidably aware of the shortcomingsof these methods of electrical connection. Their unreliability andinconvenience of use cannot be tolerated in the medical instrumentationfield. The former means of termination not only lacks convenience butdoes not in all instances adequately secure the wire so as to avoidaccidental disconnect and in addition imposes severe stresses on thewire which might result in its eventual breakage.

Another shortcoming of existing equipment is its inability to adapt tothe varying wire sizes used for connection to patients. Generally, thesemay vary from .040 inches to .125 inches in diameter. This greatly addsto the inconvenience of use as well as the potential unreliability ofthe connection. Thus, an acceptable electrical termination should graspthewires as firmly as possible against accidental disconnect,particularly in hospital environments where the wires are subject to themovements of patients, nurses, physicians, etc. In addition, it shouldbe capable of accepting different wire diameters and impose as littlestress as possible on the wires to avoid eventual breakage. TheApplicants electrical connector meets these requirements and overcomesthe problems associated with prior art terminations.

It is therefore an object of this invention to provide an improvedextra-corporeal medical instrument electrical connector. It is'anotherobject of this invention to provide an electrical connector forpositively gripping a wire without inducing undue stress. Yet, anotherobject of the invention is to provide a highly reliable convenientlyused electrical connector.

ing force on the inserted wire. The multi-jawed member is then insertedthrough a properly keyed hole in a panel of the instrument and isaffixed thereto by means assembled to its distal end. Thus, there isprovided a positive reliable clamping or attachment of the wire from thepatient to the instrumentation.

For a better understanding of the present invention together with otherand further objects thereof references is had to the followingdescription taken in connection with accompanying drawings. Its scope ispointed out in the appended claims.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a partial cross sectionalview showing the connector attached to and through the panel of amedical instrument.

FIG. 2 is a partial cross sectional view of the multijawed member of theconnector.

FIG. 3- is a side elevational view of the multi-jaw member of FIG. 2looking at the wire receiving end of the member.

FIG. 4 is a side elevational view of the distal or opposite end of themulti jawed member from that of FIG. 3.

Like symbols are used to identify the same parts in the differentdrawings and views. It is intended that these drawings display thepreferred embodiment of the Applicants invention but in no way delimitits scope.

DESCRIPTION OF THE PREFERRED EMBODIMENT With reference to FIG. 1 thereis shown an electrical connector having a resilient multi-jawed member 2composed of an electrically conductive material, for example, a materialsuch as phosphor bronze or berrylium copper. Multi-jawed member 2 is ofgenerally cylindrical geometry with the jaws forming or defining anaxially aligned channel for accepting or receiving a wire 7 insertedtherein. The portion of multi-jawed member 2 located at the end intowhich the wire 7 is inserted .has an outer surface inclined at a desiredangle. The inclined surfaces are achieved by forming this end of member2 to a generally frusto-conical geometry. The inclined plane permits theapplication of inwardly deforming forces upon the jaws, thereby exertingcompressive clamping forceson the inserted'wire 7. The apex of thisfrusto-conical portion of member 2 is located forwardly of the jawopenings.

The jaws themselves of member 2 are formed by orthoganal centrallyaligned sawcuts'extending axially a predetermined distance of the member2. The axial extension of the sawcuts is selected so as to provide thenecessary resiliency for the jawsas well as required integrity orstrength of member 2 itself.

Member 2 may be more fully described with reference to FIGS. 2, 3, and4. FIG. 2 shows a member fabricated most conveniently from a pieceof'bar or rod stock. The inclined surfaces at the jaw end of the memberare formed by a frusto-conical shaping. The jaws themselves are producedby orthoganal centrally located sawcuts 17 extending a predetermineddistance along the axis of the member 2. The opening 12 for wire 7 isformed by a drilled hole normally coextensive with the sawcuts. For easeof wire 7 insertion a relieved or counter sunk area 18 is formed at theopening 12.

The depth of the sawcuts, the selection of the material and the undercutarea 14 of member 2 provides the jaws with the necessary resiliency andstrength to produce the desired clamping action. The diameter of theopening or channel 12 is determined by the maximum diameter of the wire7 to be inserted. An interior chamber 19 is formed or bored withinmember 2 extending fromthe distal end a predetermined distance. Chamber19 provides adequate clearance for-insertion of wire 7 as well asproviding a channel along which surfaces engaging threads may be formedat the distal end of member 2.

FIG. 4 shows an end view of the wire 7 receiving end of member 2. Theorthoganal cross sawcuts 17 are shown forming the jaws, in this instancefour jaws, and the channel or wire receiving opening 12 is clearly shownas a drill or otherwise formed opening. The undercut or relieved portionof the jaws about the channel 12 is indicated by surface 18. A threadedor serrated internal portion 16 of the jaws defining the channel 12 isprovided to assure intimate contact with wire 7 and positive clamping orgripping thereof.

in describing the distal end of member 2, reference can best be made toH6. 3. FIG. 4 shows bearing surfaces 13 located on each side of member 2and formed by relief cuts axially extending from the distal end ofmember 2 to the bearing surface 13. The bearing surfaces 13 compriseshoulders extending outwardly from the side walls of the distal end orportion of member 2. The internal threaded portion 15 formed onthedistal side walls of chamber 19 is provided to permit mounting of thedevice, to the panel 4.

Again,'returning to FIG. 1 there is shown a collet member comprising afirst member 1 and a second member 3 peripherally mounted about member2. Second member 3 is threaded to member 1 thereby movably engaging it.Preferrably, the collet is made of electrically insulative material suchas nylon or other suitable plastic. However, in instances where suchinsulation is not required, the collet may be suitably fabricated from ametal or conductive material. Collet member 3 is of generallycylindrical shape having an internal portion generally complimentarywith the inclined surfaces 11 of member 2. The angle of these inclinedcomplimentary surfaces is suitably selected in the area of approximately15 with respect to the axis of the wire receiving channel 12. This angleof course may be varied to provide for variations in desired travel oradjustment provided by collet member 3. Obviously, as the angle of theinclined surfaces are altered the force derived from a given movement ofcollet member 3 will proportionally vary. Of course, binding'or selflocking bearing angles must be avoided. The relative movement of colletmember 3 with respect to member 2 is provided by 'its' threadedengagement with collet member 1. Aforward disengagement of collet member3 from collet member 1 produces a relief of the compressive forces andan opening of channel 12, while the inverse is true upon increasedengagement of mating threaded portion 8.

Collet member 1 is again of generally cylindrical geometry havingsufficient internal relief to accept insertion of the distal portion ofmember 2. The complementary geometry of collet member 1 with thegeometry of the distal end of member 2 provides both bearing surfacesbetween these members as well as a locking or keying function. it is, ofcourse, necessary that collet member 1 remain affixed to or stationarywith respect to member 2 if the necessary relative travel between colletmember 3 and member 2 is to be achieved. Of course, other means ofkeying thesernembers together may be utilized such as pinning or perhapseven integral construction or fabrication.

A locking member 6 has a complementary threaded portion to that ofinternal threads 15 and engages the distal end of member 2 when insertedthrough an opening or aperture 9 in the panel or wall of medicalinstrument 5. The aperture 9 is of complementary geometry or shape withrespect to the distal end of member 2 to provide keying or locking withrespect to the panel 4.

.In the illustrated instance of afeed through electrical connector andwhere the panel member 4 is of electrically conductive nature a suitableelectrically insulative ferrule must be placed about the bearingportions of the assembly to prevent electrical contact with the wall 4.Any suitable electrically insulative material such as nylon or mylar'may be used to achieve this purpose, and such ferrule are easilyfabricated or purchased. in a feed through application the lockingmember 6. is of course fabricated from'a suitable electricallyconductive material and in most instances will match the material of thejaw member 2. A post or other electrical junction is provided on thelocking member 6 for the purposes of electrical connection internal ofthe extracorporeal medical instrument 5. If of course electrical contactis desired with wall 4 such as in the instance of a ground connection,the insulative ferrule may not be necessary and likewise in thesituation where the panel 4 is non-conductive.

in normal use a wire extending from the body of the patient is insertedthrough channel 12 internal of memher 2. After insertion the colletmember 3 is adjusted to greater engagement with collet member 1 therebybearing the internal frusto-conical surface of collet member 3 againstthe complementary surface of the jaw member 2. As engagement of thecollet members is increased a compressive force is exerted against wire7 driving the serrations or threads 16 into the wire thereby positivelyengaging it. The entire assembly is affixed to the medical instrument 5by extending the distal end of the member Zthrough a complementaryaperture 9 and engaging it with locking member 6. As the engagement ofthe threaded portion 15 with locking member 6 is increased a bearingsurface on collet member 1 is drawn up against wall 4 as is an appearingbearing surface on locking member 6. The locking member 6 is adjusteduntil the desired bearing or locking forces exist against the wallmember 4, additional locking members such as lock washers or deformableelements may be included in the assembly to assure positive engagementof the wall 4.

The Applicants invention provides a reliable and versatileelectricalconnection for wires extending from a patient to a remote medicalinstrument. It is capable of convenient use and may accept wires or pinsof different diameters without the need of a tool. It provides excellentelectrical insulation against accidental connection to adjoiningterminals.

The electrical connector herein described is illustrative of theApplicants invention and it is intended that those modifications obviousto one skilled in the art be included within its scope.

We claim:

1. An electrical connector adapted for high reliability operation inmedical electronics usage to couple electrical conductor leads havingcylindrical surfaces from instruments sensing bodily conditions to aninstrument panel having apertures said connector comprising: amulti-jawed connector member having an internal, axially aligned boretherethrough, said jaws being formed by radial axially aligned slotsextending a substantial portion of the axial extent of said connectormember, said member having a wire receiving end and a panel terminatingend, said member at said wire receiving end having a substantiallyfrusto-conical external surface and said bore having a substantiallycylindrical surface, said terminating end including first means forkeying said connecting member into one of said apertures of said panelto prevent relative rotatary motion of said connector in said panel orsaid wire during connection; a collet member adapted to be received oversaid connector member, said collet member having an axial boretherethrough complementary to said connector member at one end andadapted at said other end with a frusto-conical surface complementary tothe frusto-conical surface of said connector member, whereby rotarymovement of said collet member causes relative axial movement of saidcollet member toward said connector member and panel to cause saidsubstantially cylindrical surface of said bore to mate with and close ona length of said cylindrical wire equal to a considerable portion ofsaid axial extent and make a secure electrical and mechanical connectiontherewith, said collet member including a first member including secondkeying means adapted to cooperate with said first keying meansof saidconnector member. preventing relative rotary motion of said conductorand said connector member, and a second member threadingly engaged withsaid first member, said second member including said frusto-conical boreand adapted to be received over said connector and said first member.

2. The connector of claim 1 wherein said frustoconical surfaces aredisposed at an angle of approximately 15 to the axis of said cone.

3. The connector of claim 2 wherein said connector and keying means areof electrically conductive material.

4. The connector of claim 3 wherein said first and second collet membersare of electrically insulative material.

5. The connector of claim 4 wherein said channel may receive said wirehaving a diameter between approximately 0.040 and 0.125 inches.

1. An electrical connector adapted for high reliability operation inmedical electronics usage to couple electrical conductor leads havingcylindrical surfaces from instruments sensing bodily conditions to aninstrument panel having apertures said connector comprising: amulti-jawed connector member having an internal, axially aligned boretherethrough, said jaws being formed by radial axially aligned slotsextending a substantial portion of the axial extent of said connectormember, said member having a wire receiving end and a panel terminatingend, said member at said wire receiving end having a substantiallyfrustoconical external surface and said bore having a substantiallycylindrical surface, said terMinating end including first means forkeying said connecting member into one of said apertures of said panelto prevent relative rotatary motion of said connector in said panel orsaid wire during connection; a collet member adapted to be received oversaid connector member, said collet member having an axial boretherethrough complementary to said connector member at one end andadapted at said other end with a frusto-conical surface complementary tothe frusto-conical surface of said connector member whereby rotarymovement of said collet member causes relative axial movement of saidcollet member toward said connector member and panel to cause saidsubstantially cylindrical surface of said bore to mate with and close ona length of said cylindrical wire equal to a considerable portion ofsaid axial extent and make a secure electrical and mechanical connectiontherewith, said collet member including a first member including secondkeying means adapted to cooperate with said first keying means of saidconnector member, preventing relative rotary motion of said conductorand said connector member, and a second member threadingly engaged withsaid first member, said second member including said frusto-conical boreand adapted to be received over said connector and said first member. 2.The connector of claim 1 wherein said frusto-conical surfaces aredisposed at an angle of approximately 15* to the axis of said cone. 3.The connector of claim 2 wherein said connector and keying means are ofelectrically conductive material.
 4. The connector of claim 3 whereinsaid first and second collet members are of electrically insulativematerial.
 5. The connector of claim 4 wherein said channel may receivesaid wire having a diameter between approximately 0.040 and 0.125inches.